Little description of the difference between snap caps (uses a spring or rubber primer) vs dummy rounds. These are purpose driven. If you're doing a lot of training for misfires and malfunctions and wants something that lasts, use the dummy rounds. If you're a gunsmith and diagnosing the firearm or if the firearm is vintage you may want to use snap caps but are not meant for a crap ton of extractions done hard. Wear and tear would be too great.
